It is common to attach a decorative flexible covering, such as carpets, to rigid supporting substrates such as floors, made of wood or concrete. It is often desirable, or even required, to fasten carpet to the flooring which it covers and a variety of attachment methods have been developed over the years.
Carpet can be glued directly to flooring. This is often the approach taken in an institutional setting in which the underlying flooring is concrete and liquid glue is applied across the entire concrete area to be covered. This approach has the advantage that, so long as the adhesive bond provided between the carpet and flooring remains intact, the carpet cannot buckle. Of course, adjustment or replacement of such carpet can be difficult in the sense that previously applied glue might be required to be stripped from the flooring and new glue applied. In addition, such glues often contain volatile organic components that are banned in some places or are required to be ventilated, in other places.
Another approach taken to installing wall-to-wall carpet involves the use of "tackless strips", which are wooden strips having angled tacks driven upwardly therethrough. The strips are secured around the perimeter of the area to be covered, often by nailing them into wooden flooring, and the carpet is stretched over the tacks. This approach has the advantage that the carpet can be restretched to remove a buckle that develops, and the carpet and underpad, not being permanently adhered to the flooring can be removed without being destroyed. However, stretching is a labour intensive art which makes installing wall-to-wall carpet by this method relatively expensive. This approach also avoids the use of volatile organics, but some difficulties can arise in installing tackless strips to concrete.
More recent approaches involving the use of Velcro-type fasteners have been described in the patent literature: Germany 7,029,524 (Aug. 8, 1970, Velcro France); U.S. Pat. No. 3,574,019 (Apr. 6, 1971, Girard); UK 1,546,901 (May 31, 1979, Allied Chemical Corporation); U.S. Pat. No. 4,822,658 (Apr. 18, 1989, Pacione); U.S. Pat. No. 5,191,692 (Mar. 9, 1993, Pacione); U.S. Pat. No. 5,382,462 (Jan. 17, 1995, Pacione); and U.S. Pat. No. 5,479,755 (Jan. 2, 1996, Pacione).
U.S. '658 from the same inventor describes a wall-to-wall installation in which hooked strips are secured by pressure sensitive adhesive around a room perimeter and at the carpet seams. A carpet having loops across its backside is cut to fit the room and the loops engage the hooked tape. U.S. '692 describes a method for seaming a carpet such as the one described in U.S. '658. Both of these patent specifications also disclose advantages obtained through the use of a cover for the hooked tape, a primary advantage being that such a cover prevents premature engagement of the hooks and loops to permit proper placement and adjustment of the carpet without the need for disengaging prematurely engaged hooks and loops during installation. This prior approach provides the advantages of installing strips at the perimeter and seams of a carpeted area, particularly that the carpeting can be lifted without being destroyed and the avoidance of the use of compounds containing volatile adhesives.
The "holy grail" of carpet and other decorative covering, would be a system which when laid had such mass and stability as to require little or no attachment to the underlying substrate and which can be installed over existing substrates without the necessity of the removal of existing covering. However for transportation in trucks and to physically fit into a site, such as a room, such a system has to either provide for sufficient flexibility so that it can be rolled or, if rigid, a way of assembling modules so as to form a contiguous mass in situ with sufficient mass and stability to remain in place with minimal detachable attachment or perhaps no attachment, particularly when dealing with different existing floors or flooring surfaces to be covered.